Simplify keyboard tracking logic.

samples/Unity.Mvvm.ToDoList/Assets/Scripts/UIElements/MobileInputAdaptivePage.cs

@@ -12,13 +12,13 @@ namespace UIElements
 {
  public class MobileInputAdaptivePage : VisualElement, IDisposable
  {
+ private bool _isActivated;
  private float _parentHeight;
  private float _initialPaddingBottom;
  private float _defaultPaddingBottom;
  private float? _paddingBottomWithKeyboard;
  private MobileInputDialogController _inputDialog;
 
- private AsyncLazy _trackKeyboardActivityTask;
  private CancellationTokenSource _cancellationTokenSource;
 
  public MobileInputAdaptivePage()
@@ -29,14 +29,21 @@ public MobileInputAdaptivePage()
  }
  }
 
+ public bool IsActivated => _isActivated;
  public float OffsetFromKeyboardPx { get; set; }
- public bool IsActivated => _trackKeyboardActivityTask is { Task: { Status: UniTaskStatus.Pending } };
-
+
  public async UniTask ActivateAsync()
  {
+ if (_isActivated)
+ {
+ return;
+ }
+
+ _isActivated = true;
+
  if (IsScreenKeyboardSupported())
  {
- ActivateKeyboardTrackingAsync().Forget();
+ TrackKeyboardActivityAsync().Forget();
  }
 
  SetVisible(true);
@@ -48,6 +55,13 @@ public async UniTask ActivateAsync()
 
  public async UniTask DeactivateAsync()
  {
+ if (_isActivated == false)
+ {
+ return;
+ }
+
+ _isActivated = false;
+
  if (IsScreenKeyboardSupported())
  {
  _inputDialog.HideScreenKeyboard();
@@ -89,25 +103,15 @@ private void OnLayoutCalculated(GeometryChangedEvent evt)
  parent.visible = value;
  }
 
- private async UniTaskVoid ActivateKeyboardTrackingAsync()
- {
- if (_trackKeyboardActivityTask?.Task.Status.IsCompleted() ?? true)
- {
- _trackKeyboardActivityTask = TrackKeyboardActivityAsync().ToAsyncLazy();
- }
-
- await _trackKeyboardActivityTask;
- }
-
- private async UniTask TrackKeyboardActivityAsync()
+ private async UniTaskVoid TrackKeyboardActivityAsync()
  {
  _cancellationTokenSource = new CancellationTokenSource();
 
  try
  {
  var cancellationToken = _cancellationTokenSource.Token;
 
- while (cancellationToken.IsCancellationRequested == false)
+ while (_isActivated)
  {
  if (TouchScreenKeyboard.visible == false)
  {